Man Hee Rhee
Kyungpook National University, South Korea
Title: Baicalein inhibits tumour cell-induced platelet aggregation and suppresses pulmonary tumor metastasis
Biography
Biography: Man Hee Rhee
Abstract
Recently, the importance of platelet activation in cancer metastasis is generally accepted and development of new platelet inhibitor with minimal adverse effect is a promising area of targeted cancer therapy. Baicalein is a one of functional ingredient derived from the root of Huangqin. Its pharmacological effects including anti-oxidative and anti-inflammative effects have already been shown. However, effect on platelet activation of this molecule is scarce. Therefore, we investigate the effects and its molecular mechanisms of baicalein on various agonists, including tumor cell, -stimulated platelet activation and pulmonary cancer metastasis.
Effects of baicalein on agonist-stimulated platelet activation, granule secretion and adhesion molecule expression, cyclic-nucleotide release, VASP and MAPK phosphorylations were evaluated. Indeed, influences of baicalein on platelet aggregation induced by tumor cells and adhesion of cancer cell-platelets were evaluated. Finally, after acute toxicity test, we also examined the anti-metastatic activities of baicalein using relevant in vivo metastasis models.
Key result: Baicalein inhibited various agonists such as collagen, ADP, and thrombin-induced platelet activation in a concentration dependent manner. Agonist-induced granule secretion (P-selectin expression, ATP release), mobilization of intracellular [Ca2+]i and glycoprotein â…¡a/â…¢b expression were also reduced in baicalein-treated platelets. Baicalein also attenuated ERK2, p38 and Akt activation and enhanced VASP phosphorylations that was reversed by H-89 (PKA inhibitor). Moreover baicalein attenuated C6 rat glioma tumor cells-induced platelet aggregation in vitro and CT26 colon cancer metastasis in vivo.
Baicalein shows broad anti-platelet properties. This feature might have therapeutic implications for the prevention of cancer metastasis